# What is the electron configuration of an iron atom?

$1 {s}^{2} 2 {s}^{2} 2 {p}^{6} 3 {s}^{2} 3 {p}^{6} 4 {s}^{2} 3 {d}^{6}$

#### Explanation:

To write an electron configuration for any element you'll need to apply the Aufbau principle and use a diagonal diagram. Both are explained in the video below.

Of the elements discussed in the video, iron is most like Sc, but iron has 5 more electrons in the last subshell which is filled with electrons making its configuration end in $3 {d}^{6}$ rather than $3 {d}^{1}$

Hope this helps!